[U-Boot] fw_setenv usage for multiple copies of U-Boot Environment Variables

[Detlev Zundel <dzu@denx.de>]

Hi Amarendra,

> Hi Wolfgang Denk,
>
> Thank you for the reply. Yes I am talking about "redundant environment".
>
> If we have four "redundant environment" copies in the same
> partition(mtd1)... Does the below fw_env.config configuration hold
> good ?

U-Boot cannot cope with more than two redundant copies.

> ####################################################
> # File: fw_env.config
> # Configuration file for fw_(printenv/saveenv) utility.
> # Up to two entries are valid, in this case the redundand
> # environment sector is assumed present.

Read the text carefully: "Up to two entries are valid"....

>
> # MTD device name       Device offset   Env. size       Flash sector size
> /dev/mtd1               0x00000         0x02000         0x20000
> /dev/mtd1               0x20000         0x02000         0x20000
> /dev/mtd1               0x40000         0x02000         0x20000
> /dev/mtd1               0x60000         0x02000         0x20000
> ####################################################

On the other hand why exactly do you need four redundant environments?
The idea behind redundant environments is that a powercut _while_
updating one copy can be handled by having a backup copy.  It is _not_
meant to handle faulting devices in any way.

Cheers
  Detlev

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